In the midst of growing concern about an obesity epidemic that includes children, worried parents should tread lightly.

Even when love and good intentions drive comments and corrective actions, it may be taken as body shaming, experts say. And it can lead to self-hatred.

A new survey shows 94 percent of teen girls and 64 percent of teen boys have been ridiculed over how they look. Among adults, 90 percent say someone mocked an aspect of their appearance — most common targets are bellies and legs. The survey was conducted for sports and exercise equipment rating company Fit Rated.

"Our body image plays a huge role in how we all feel about ourselves," says Alexis Conason, a psychologist specializing in overeating and body image in New York City who does research at Mt. Sinai Medical Center. She says youths are developing their sense of self and body shaming can warp self-image and launch eating disorders and serious physical and psychological problems, including mood disorders and anxiety.

Who body shames may be a surprise. Media provide the most unrealistic, altered and idealized images of what is good-looking. But targeted criticism typically comes from people close to the one being shamed — and mothers top that list, which includes friends, dads, co-workers, dates and others. Even grandmas make others feel bad about their looks.

"It is heartbreaking because, for the majority of clients with whom I have worked who have been trying to kick unhealthy food and exercise habits, the body shaming almost invariably started in childhood," says Ramani Durvasula, professor of psychology at California State University, Los Angeles and author of "You Are Why You Eat: Change Your Food Attitude."

For parents who grapple with how to deal candidly about weight and other body-image issues, child health experts advise that focusing on the larger issue of physical and mental health is key.

"We focus on healthy behaviors, and if we find success in that, weight takes care of itself," says Dr. Stephen Pont, medical director of the Texas Department of State Health Services.

World built for norms

"Culturally, we are in a society that promotes the idea that our worth is tied to our appearance. The costs are really deep," according to Conason, who says children internalizing that as young as preschool "may worry about becoming fat. When we internalize, we get caught in a bind," she adds. "We're never good enough; the ideal isn't possible."

Messages that make one feel bad can be obvious or subtle: At school, peers may exclude someone, or someone chides a person who looks overweight for buying snacks. Conason notes the world is not built for larger people, so seats in restaurants or on planes may be too small, causing embarrassment.

At home, parents say things like "You'd have more friends if you lost some weight" or "You would be so pretty if you weighed less."

"Our society still views fat jokes as acceptable and body shaming happens both egregiously and openly, but also in a million subtle ways when an overweight person gets a laugh track or is viewed as the sidekick or not worthy of a date," says Durvasula.

"Clinically, it takes a long time to build people back up from these experiences and can feel impossible when it is ongoing," she adds.

Even doctors do it. Conason's examples of body shaming include a patient who looks overweight complaining of a sore throat and being told, "You should really lose some weight."

"If you are in a larger body, often that's all people see. It's a funny combination of being seen and not seen," she says. "Size is all anyone notices."

That's what one who is overweight notices, too, says Katherine Pagano, a doctoral student at the University of Utah who researches body shaming. Social comparison theory — people trying to assess how they stack up against others — strongly suggests those who compare themselves "have lower body-image perception, lower confidence, lower self-worth and are more apt to develop eating disorders, exercise obsession and use of anabolic steroids (more common for males.)"

Plus, those who have been body shamed are 32 percent more likely to do the same thing to someone else, according to the survey.

The conundrum

Here's the challenge, though: Millions of American children and adolescents are overweight, and that can result in a greater risk of coronary artery disease, diabetes, depression and other medical woes. The American Academy of Pediatrics says more children suffer from obesity than any other chronic condition, with 17 percent ages 2-17 obese and one-third at least overweight. In poor communities, two-thirds of children may be overweight.

Even doctors struggle with how to address it.

The American Psychological Association says that the damage to one's psyche and health from being heavy is so great that obesity and overweight must be addressed, especially in children.

But the American Academy of Pediatrics warns parents and others to be careful in addressing the issue with their children.

"We are focused on the whole health of the child, which includes brain and behavioral health and their self-esteem and absolutely on their physical body health as well," says Pont, of the Texas Department of State Health Services, who led the group that wrote the policy statement for the academy on how pediatricians should work with families of overweight children and teens.

"Being at a healthy weight or at least monitoring where folks are is an important part of that as well, but we really want to be very mindful of the weight stigma that does exist in our society and try to turn away from that."

He notes negative motivations to jump-start behavior changes make people feel bad and aren't effective. And kids challenged by weight may already struggle with low self-esteem, he says, referring to research that found adolescents with obesity reported a quality of life comparable to kids with cancer.

Being too thin can also be unhealthy — and may also lead to body shaming. Janet Ruth Heller, president of the Michigan College English Association and owner of a book store bearing her name in Portage, Michigan, was bullied as a child for being thin.

"Because of that daily name-calling, I thought there was something terribly wrong with my body," she says. "I did not know how to stop the girl who bullied me because there was a grain of truth in her insult. After school, I would go home and cry."

She has friends who were body shamed for excess weight, for being tall or short or having different skin color or a disability. All leave scars. The bullying she endured made her distrust peers. "It took years and psychotherapy for me to heal from these verbal attacks."

And weight is just one measure of overall health. Kids and adults who are visually at a healthy weight may engage in really unhealthy behavior, like high-risk sexual activity or alcohol abuse, says Pont.

"We are making a big mistake by focusing on weight and body size as a metric of health and desired caloric intake," warns Catherine "Kate" Bell, a psychologist on Harvard Medical School's faculty.

She said parental or health provider focus on size or weight usually kicks off a diet-binge cycle. It's statistically shown the chance of an eating disorder goes up as much as 18-fold, she asserts. Children who diet — and even toddlers are sometimes put on diets — may end up weighing more. "There is a direct link between obesity and early dieting and it's far more pronounced in children than it is in adults."

If children believe size determines self-worth and then don't reach their weight — "even if they are eating 'perfect'" — may eat far below caloric recommendations, with ramifications for health and brain and body development, says Bell.

Parents and others also fail to consider basic biology sometimes, she adds. Young girls before puberty plump up, she says. "They need energy for their bodies to develop processes. If you don't intervene, they will get smaller when their hormones come. Trust their bodies to get bigger and smaller according to what the endocrine system is doing."

Powerful parenting

Sharri and Ryan Morley have three kids, Isla, 6; Penn, 4, and Hadley, 2, and they're raising their kids to love healthy foods and being in motion. Dinner always contains grains and bright-colored combinations of food, she says.

"They don't know the underpinnings of diet, just what you eat makes you feel good," Sharri says.

They bike, walk, are learning to ski and they play outside a lot.

"We like to be out enjoying some level of activity. There's something to go and see and do that's fun and interesting wherever you are," says the Salt Lake City mom.

Pont discusses children's weight with parents and patients in these terms: Some health complications are genetic or age-related and you can't change that. "You can work only on healthy behaviors," he says.

That's how experts say to couch it: Being healthy.

Conason hopes parents will monitor themselves and recognize research says the teasing parents do about a child's weight is harmful. Encouraging a child to diet to lose weight "increases the risk of low-self esteem and all its effects."

"One of the most powerful things parents can do is model acceptance of body diversity at home, starting young. Read story books with characters with different shapes and sizes," she says. "Talk openly about differences, not as good or bad, but just different. … Some people are larger, some taller, some darker."

Implement changes for the whole family, without singling out one child. That's sensible anyway. "Children in the U.S. on average have gotten a lot larger, so visually it's harder to tell who's at risk and who isn't," Pont says. But everyone benefits from more exercise and good nutrition.

He tells parents to think small, making moderate nutritional changes and paying attention to family activities that are easy to start and enjoyable. Do them as a family and engage the kids in the process, to reduce resistance and resentment.

Because one kid "can drink 25 sodas a day and be skinny. Another kid can drink only water and be heavier," Bell says parents should be food guides who eat with kids as often as possible, modeling healthy behaviors with food, from good nutrition to enjoying its social aspects and helping kids learn internal signals like satiety.

Meals should include enough food that everyone can feel full, but parents choose which foods, ensuring nutrition and food group variety. Bell suggests talking with young children about how you feel when you eat, such as telling them about the healthy foods you like or the discomfort when you eat too much.

"Just do what's healthy and actually feels healthy, too, then weight stabilizes and disordered eating falls," she says. "It may be a higher weight than you want it to, but your health marker should resolve, too."

Young bodies like to move and parents can capitalize on that. Get out like the Morleys and do things, not to be thin, but "because it makes me feel good."

The nation's weight gain has societal issues that need addressing for large-scale impact, Pont says. Families who can only afford to live in a neighborhood with a higher crime rate may not have parks kids can safely play in. Low-nutrition food is often cheaper than healthy food.

Families have options, like tap water, which is readily available "cheaper than anything you can buy at the store. Drinking more water is in everyone's reach." But social policy could do more too, he says.

For parents, the challenge is finding a balance, Pagano says. "Parents have to know when to push and not to push."